2639-18-1Relevant academic research and scientific papers
One pot solvent-free solid state synthesis, photophysical properties and crystal structure of substituted azole derivatives
Du, Yanting,Wan, Zilu,Chen, Lianqing,Wu, Lamei
, p. 315 - 325 (2019/05/27)
A solvent-free solid state method has been developed to synthesize three series of substituted azole derivatives (including 1,3,4-oxadiazole, 1,3,4-thiadiazole and 1,2,4-triazole) in high yields by condensation cyclization of N,N′-bishydrazide derivatives with corresponding cyclization agents, respectively. This general method avoids the use of organic solvents, saves cost and resources, simplifies post-processing and increases reaction rates. These compounds have been fully characterized by 1H NMR, 13C NMR, elemental analysis and MS. The structure of 2,5-di (4-tertbutylphenyl)-1,3,4-oxadiazole has been determined by single crystal X-ray diffraction analysis. The cell parameters are as follows: monoclinic crystal system, Cc space group, a = 18.735 (2) ?, b = 6.3375 (8) ?, c = 16.824 (2) ? and α = γ = 90°; β = 98.292 (2). The electronic absorption and fluorescent properties of these compounds have been systematically investigated for the first time. The relationships between heterocyclic structures and photophysical properties have been discussed. The alteration of emission and absorption wavelengths can be elucidated by hybrid atoms' electronegativity and Substituents' Hammett constants. This approach proposes a novel insight to provide a great number of novel substituted azole derivatives with good photophysical properties by a general green method.
Synthesis method of 2,5-disubstituted-1,3,4-oxadiazole
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Paragraph 0007; 0029, (2018/08/04)
The invention discloses a synthesis method of a drug intermediate, namely, 2,5-disubstituted-1,3,4-oxadiazole. 2,5-disubstituted-1,3,4-oxadiazole is synthesized with a one-pot method under the photocatalytic action with simple hydrazide compounds as raw materials. 2,5-disubstituted-1,3,4-oxadiazole can be produced through a reaction at the room temperature with a common halogen lamp as a light source, eosinY as a catalyst, potassium carbonate as an additive and ethanol as a solvent. The method has the characteristics that the raw material source is simple, the reaction condition is mild and the like.
Efficient oxidative cyclisation of acid hydrazides to 2,5-disubstituted 1,3,4-oxadiazoles catalysed by Bu4NI with t-BuOOH as oxidant
Gao, Peng,Wei, Yunyang
, p. 506 - 510 (2013/09/12)
Acid hydrazides or araldehyde N-acylhydrazones can be converted in good yields to, respectively, symmetrical or unsymmetrical, 2,5-disubstituted 1,3,4-oxadiazoles at 60 °C by a Bu4NI-catalysed procedure which requires the presence of a base and 2.5 equiv. of t-butyl hydroperoxide.
